Underground tunnel construction



May 29; l945- c. D JAcoBs UNDEGRQUND TUNNEL CONSTRUCTION 3 sheets-sheet 1 Filed April 25, 1942 l ful |.1 l

May 29,'1945. c. D. JACOBS UNDERGROUND TUNNEL CONSTRUCTION 3 Sheets-Sheet 2 Filed April 25, 1942 f, w m J ,w m f a 8 l W May 29, 1945. C D. JACOBS 2,377,012

UNDERGROUND TUNNEL CNSTRUCTION I Filed April 25, 1942 3 Sheets-Sheet 3 Patented May 29, 1945 `lllNflTED STATES PATENT vforrlcE,

` UNDERGRQUND 'nUNNELooNsTUcrIoN charlesn. Jacobs, Pikeville, Ky. Application April 25, 1942, seriellen. 440,553 (orti- 425` 21 Claims.

This invention relates to improvements in underground tunnel construction and is particularly concerned with the formation `of varches or otherroofs. l f

A'major `object ofthe invention is to control :the strata above the tunnel roof and in this connectioncontemplates construction of the tunnelv roof `insections with only `a ysmall area above fthe roof exposed at any one time so that each section `of Ythe-roof arch -is'keyed to the side walls and issel-f-supporting. l f

A :further obj-ect of the invention is. to :utilize the :rock -or-other earthy material beneath-the tunnel roofto Isupport the same untilthe `roof is completed, whereupon the underlying 4balance ofthe tunnel is excavated `to the desiredsizelof thestructure. l i

A further object of the invention is to afford vprotection. for the green concrete jformingl the tunnel roof so as :to `prevent damage tothe concrete Awhen shooting out or blasting the underlying materialto complete the tunnel.l

vAnother object of -the vinvention is `to provide ess of its construction and looking downwardly; Figis a side elevational view of 'theileft hand endof Fig. f4 `showing Vtheftemporary waste chutes a novel methodof constructing blindftunnels, i. 1e.,

tunnels dug or blastedinthe side ofan embankmentor working face and having the innermost end thereof closed.

The invention in general involves a simple method of ,modified long-.wall mining and back filling with reinforced concrete.

While the invention is applicable to the con-- struction of tunnels or underground structures in general, .the principles thereof have `been found tobeparticularly applicable andare herein .illustrated 4and `described in connection with .theformation of ,anunderground dry `dock in which ships may be housed, protected .from damage Aby bombs .and invisible vfrom overhead, together with materials necessary to repair and `upkeep of the ships'. "This particular type of structure -is also ideally suited for airplane hangars, oil `and munitions storage, as well as for protectionof humans. v H..

'Referring to "the accompanying Vdrawings wherein a particular embodiment of the inventionas aforesaid "has been selected for exempliflcation: 1

Fig.`1 is a vertical section of a completed dry dock or tunnel;- v i iFig. 2 isV a plan viewof Fig. 1" partly broken awayto show thetunnel structure; Fig. /3 lis an end view of Fig. 1 looking into the y tunnel structure;

Fig. 4 is a broken substantially horizontalsection takenthrough theroof area during the procfor the discharge of material delivered thereto fromjthebel-t conveyors vdisposed in the llongitudinalpassageways; A

Fig; 6 is )a Afragmentary view similar to Fig. but yshowing a-iportion ofthe roof completed;`

` Figs? isasectional vview taken `on the line 1 1 0f 6AF'gsi;

Fig. 8 fis va sectional view taken lon the line ^88 of'FigfG before excavation of the materialunderlyingft'he roof and illustrating ythe, provision yof collapsible zmeans between the roof and underlyingsupport; and h j FigsQisa sectional view taken Ion the line 9'9 of -Iligfg` After the `location for the structure has been determined and prospected by core .drilling to ascertain definitely that vthe local structure lhas mechanical strength tosupport the arch, a'plli'- rality of spacedfpassageways A, B and yC are driven inwardly froma working ',face or embankment for 'th-e fu'll lengthofthedry dock or.other tunnel structure. 'As the passageways `A, B and C are drivenzconveyor "belts Ill lmay jbe placed' therein and at'the inner endcross cuts or cross Apassage-- ways indicated at Dr are driven `at right angles to-*conn'ectthe jpassageways A and B and B and C. "Chain conveyors` yIl are then placed in the passages 'D .near the out-by rib to deliver. rock to .the belt lconveyors in the ,passageways A and C as mined. 'Temporary waste chutes indicated at vlI2 are constructed convenient to the openends r of the passageways A; B/and C as best illustrated in Fig.` 5. f Y A `,modified 'longfwall face has now been developedf Excavation of lthe remaining .roof area for the construction of the roof archsections may l then be linitiatedby 'drilling and .shooting .on the out-by rib as indicated at therighthand end of Fig. 4. For ordinary purposes I have found-that the various Iarch sections may be 4vconveniently formed kin widths .of '8 `vto '10 feet and thebroken lines `in Fig. 4 extending. transversely l`of the Atunynel indicate .the positioning of rsuccessive arch sections Working toward the entrance .to `the str-ucture.

Fig.6 illustrates the roofarch as partiallycompleted; ithe completed sections .being indicated at i4. `It 'will be noted thatas thefvarious concrete sections are completed, 'the conveyor beltsA l0 in the vpassageways IA, Band C areshortened in order'xto operate upon the materialbeing exca-y vatedfromthe next succeeding sectionarea. LIn

Fig. 6 a form indicated at I5 has been placed for the pouring of concrete admitted by the conveyor belt I in the passageway B for the formation of the next succeeding arch section adjoining the completed sections I4.

The invention contemplates that a small area of the tunnel structure is exposed at any one time. While the roof area as indicated in Fig. 6 may be excavated for the :width of several roof sections for convenience of operation, it will be apparent that further excavation proceeds only as each segment of the concrete arch is formed and becomes keyed to the side walls and self-supporting. In this manner no bracing or tirnbering is necessary to maintain control of the overhead material.

Further, no rock or other earthy material is removed from the area under the arch until the entire arch is completed. In order to protect the concrete arch from damage while shooting out or blasting the underlying structure in theexcavation of the tunnel area it is desirable to provide a layer of collapsible material 20 between the concrete arch sections and the underlying rock prior to formation of theseetions, Thus, when the entire arch is completed there is a continuous layer of collapsible material lying between the arch and the earth support. Prior to excavating the earth support the collapsible material is broken and removed Ithus forming a kerf or open space -below the green concrete forming the arch, .which space will prevent damage to the concrete during excavation. A convenient forni of collapsible material has been found to be second grade hollow tile which may be readily broken-and removed by hand, but it is understood that any other suitable and available material may be employed.

Excavation of the tunnel area. beneath the completed arch may be accomplished in any desired manner, for example by the use of relatively small electric shovels. This excavation is simple and inexpensive due to the great size of the face on which the shovels will be working. As excavation to the desired extent is completed, a coating of cement I8 may be sprayed on the side walls to a thickness determined by local conditions.

The completed structure illustrated in Figs. l and 2 may include if desired a lock as indicated at 22 to control the water level within the structure and a railroad 24 may be extended throughout the length of the structure for servicing the ships or other equipment which may be housed therein.

U While the invention has herein been described and illustrated with respect to the construction of arched roofs, it will be understood that the same method may be employed for the construction of flat roofs or roofs of any other desired conguration, adjusting the quantity` of reinforced concrete as necessary.

' Iclaim:

1. The method of constructing a tunnel which comprises providing a layer of collapsible material on an earth support, forming a roof immediately above said layer of collapsible material, collapsing said material to provide a kerf between the roof and the supporting earth-beneath the roof and excavating said earth to form a tunnel. 1

2. The method of constructing a tunnel which comprises providing a layer of collapsible material in the form of an arch lying upon an earth support, forming an arched roof immediately above said layer of collapsible material, collapsing said material to provide a kerf between the arched roof and the earth therebeneath and excavating the earth beneath the arched roof to form a tunnel.

3. The method of constructing a tunnel which comprises, providing a layer o-f collapsible material lying upon an earth support, forming a roof immediately above said layer of collapsible material, collapsing and removing said material from between the roof and the earth beneath the roof to provide a substantially clean kerf between the roof and the earth therebeneath and excavating the earth beneath the roof to form a tunnel.

4. In tunnel construction the improvement which comprises, providing a layer of collapsible material along a transverse section of the tunnel with the collapsible material lying upon an earth support, forming a transverse roof section above said layer of collapsible material, collapsing said material to provide a kerf between the roof section and the earth beneath the roof section, and excavating the earth beneath the roof section to form a tunnel.

5. The method of constructing a tunnel which comprises providing a layer of collapsible material along a transverse section of the tunnel with the collapsible material lying upon an earth support, forming a transverse roof section above the sai-d layer of collapsible material, repeating the aforesaid steps until the desired number of roof sections is completed to form a roof, collapsing said material to provide a kerf between the roof and the earth beneath the roof and excavating the earth beneath the roof to form a tunnel.

6. The method of constructing a tunnel which comprises forming a plurality of spaced passageways longitudinally of the tunnel, excavating a transverse section of the tunnel area communicating with said passageways to provide space for a roof section, removing the thus excavated material through one of said longitudinal passageways, introducing roof forming materials through another of said passageways and constructing a transverse roof section in at least a portion of the excavated area, repeating said steps until the desired number of roof sections is cornpleted and then excavating beneath the roof to form a tunnel. K

7. In tunnel construction Athe improvement which comprises, forming a plurality of spaced passageways longitudinally of the tunnel, excavating a transverse section of the tunnel area communicating with said passageways to provide space for a roof section and removing the excavated material through one of said longitudinal passageways, introducing roof forming material through another of said passageways and constructing a transverse roof section in at least a portion of the excavated area and then excavating beneath the roof section to form the underlying tunnel area.

8. The method of constructing a tunnel which comprises, forming a plurality of spaced passageways longitudinally of the tunnel, excavating a transverse section of the tunnel area communicating with said passageways at a point remote from the open end of said passageways to provide space for a roof section, removing the thus excavated material through one of said longitudinal passageways, introducing roof forming material through another of said passageways and constructing a transverse roof section in at least a portion of the excavated area, repeating said steps working toward the open end of said passageways until the desired number of roof sections is completed to ae'moie 3 form aroof @and thenexcavating beneathl the roof to'formatunnel. z z

9. Themethodof constructing 'an underground concrete 'wall which comprises, forming @a plurality of spaced :passageways longitudinally of the wall, excavating a transverse section of the wall area communicating withsaid passageways at a point remote from the open fend, of said vpassageways to provide space for a wall section, 'removing the excavated material through one of `said longitudinal passageways, introducing concrete wall forming materials through another of `said passageways fand constructing a transverse wall section lin-at least a portionof the excavated area and repeating said excavating, material removal and introduction steps' until the desired number of sections is completed to form a wall.

l0. The method of constructing a tunnel which comprises, forming a plurality of spaced Ypassageways longitudinally of the tunnel, excavating 'a transverse section of the tunnel area com.- municating with' said passageways to provide space for a'roof section, removing the excavated l material through one of said longitudinal passageways, introducing collapsible material and roof forming material through another of said pas-l which comprises, forming a plurality of spaced i passageways longitudinally of the tunnel, excavating a transverse section of the tunnel area communicating with said passageways to provide space for a roof section, removing the :excavated material through one of said longitudinal passageways, `introducing collapsible material and roof forming material through another of said passageways, and placing a layer of collapsiblel material in the lower portion of said space and forming a roof section in the upper portion 'of said space upon 'said layer of collapsible material, collapsing and removing said collapsible material from between the roof section and underlying earth to provide a substantially clean kerf between the roof section and the underlying earth, and then excavatingthe underlying earth to form the underlying tunnel area.

12. In tunnel construction the improvement which comprises, forming a plurality of spaced passageways longitudinally of the tunnel, excavating a transverse section of the tunnel area communicating with said passageways at a point remote from the open end of said passageways to provide space for a roof section, removing the excavated material through one of said longitudinal passageways, introducing collapsible material yand roof forming material through another of said passageways and placing a layer of collapsible material in' the lower portion of said space and constructing a, transverse roof section in the upper portion of said space upon said layer of collapsible material, collapsing said layer of collapsible material to provide a kerf between the roof section and the underlying earth and then excavating `the funderlyir-ig Aearth to .form the underlying tunnelzarea. i i

i3. The :methOdof-'Orming :a tunnelclose'd at one end 'which comprises .driving a, plurality of spaced :passageways from the open end of the tunnel longitudinally of the full length of the tunnel .toprovide fou-ter passagewaysfone at each lateral edge or `the tunnel -roof varea and a 4passageway .intermediate isaidfedges, yexcavating successive transverse sections l'of 'the 4tunnel area beginning at the closed end thereof 4across said passageways to provide ,space for-xa .layer of Icolla-ps'ible :material 4and `,roof sections, removing the excavated material through said `:outer `passageways, intrcdu-.cing collapsible and concrete roof f'ormingmaterials through said'intermediate-passafgewayl after "selected :transverse sections are excavated and placing a :layer of ycollapsible :material 'in lthe 4lower 'portion' :of 'the selected excavatedsection and orming ,1a concrete roof section in `'the :upper portion thereofiabove said layer of collapsible material, Athe :concrete `roof sections and underlying layer of collapsible material Ibeing continuous throng-lumi: the length :of 'the':tunnel, removing zsaid Vlayerfrofl collapsible materialtso provide :a kerf `between `:the Atunnel 'roof and the f unexcavated lmaterial therebenea-th and then completingzexcavation of theftunnel areato form the tunnel. 1 i

14. The method of forming an underground tunneledfdrydock which comprisesdrivingla plurality-of spaced lpassagewaysv from the `forward end 'llongi-tudinallyof 4itheffu'll"lengthaoi the dry dock tun-nel -to provide outer passageways one at each'laterail fedge o'f theTt-unnel roof area' Yand a passageway intermediate `said i edges, excavating successive transversesections of the tunnel roof area across :said passagewaysibeg'inning atrthe rearward end thereof "and 'working toward the forward end'to provide space 'for Vroof sections, removing 4the excavated material through said outer passageways, introducing concrete roof forming material through said intermediate pas? sageway after selected transverse -sectionsfare excavated-and ff'orrn'ing a concreteiroofsection in atleast `a portion 'of 'the selected excavated section, the concrete roof sections thus formed being substantially continuous throughout the length of the dry dock tunnel, then excavating the earth underlying the roof sections to complete formation of the tunneled dry dock area and nally applying a coating of cementitious material to the side walls of the tunnel.

15. The method of forming an underground tunneled dry dock which comprises driving a plurality of spaced passageways from the forward end longitudinally of the full length of the dry dock tunnel to provide outer passageways one at each lateral edge of the tunnel roof area and a passageway intermediate said edges, excavating successive transverse sections of the tunnel roof area across said passageways beginning at the rearward end thereof and working toward the forward end to provide space for a layer of col-V lapsible material and roof sections, removing the excavated material through said outer passage"- ways, introducing collapsible and concrete roof forming materials through said intermediate passageway after selected transverse sections are excavated and forming a layer of collapsible material in the lower portion of the selected excavated section and a concrete roof section in the upper portion thereof between said roof section and the unexcavated supporting material comprising the remainder of the tunnel area, the concrete roof sections and underlying layer of collapsible material being substantially continuous throughout the length of the tunnel, removing said layer of collapsible material to provide a ker between the tunnel roof and the unexcavated material therebeneath, then excavating the material beneath the roof to complete formation of the tunneled dry dock area and finally 'applying a coating of cementitious material to the side walls of the tunnel.

16. The method of constructing a tunnel which comprises providing a layer of collapsible hollow tile in the form of an arch lying upon an earth support, forming an arched concrete roof immediately above said layer of collapsible hollow tile, collapsing said hollow tile to provide a kerf between the arched concrete roof and the earth there beneath, and excavating the earth beneath said arched concrete roof to provide a tunnel.

17. The method of constructing a tunnel which comprises excavating a transverse underground section of the tunnel area, providing a layer of collapsible hollow tile in the lower portion of said excavated section, forming a concrete roof in said excavated section immediately above said layer of collapsible hollow` tile, collapsing said hollow tile to provide a kerf between said concrete roof and the earth there beneath, and then excavating said earth. v

18. The method of constructing a tunnel, which comprises: forming an underground passageway of substantially less width than the desired width of the tunnel inwardly from a working face; widening said passageway at the inner end there- -of to form a transverse chamber of a width greater than said desired tunnel width and of a height about equal to the desiredroof thickness; introducing roof forming material into said chamber to substantially ll the same to provide a transverse roof section of the desired thickness; and then excavating beneath the roof to form a tunnel.

19. The method of constructing a tunnel, which comprises: forming an underground passageway of substantially less width than the desired width of the tunnel inwardly from a working face', widening said passageway at the inner end thereof to form a transversely arched chamber of a width greater than said desired tunnel width and of a height about equal to the desired roof thickness; introducing roof forming material into said chamber to substantially iill the same to provide a transversely arched roof section of the desired thickness; and then excavating beneath the arched roof Ato form a tunnel.

20. The method of constructing a tunnel, which comprises: forming underground passage means of substantially less width than the desired width of the tunnel inwardly from a working face; widening said passage means at the inner end thereof to form a transverse chamber of a width greater than said desired tunnel width and of a height about equal to the desired roof thickness; introducing roof forming material into said chamber to provide a transverse roof section of the desired thickness; successively forming similar transverse chambers working toward the outer end of said passage means and successively introducing roong material into said chambers to form successive roof sections'until the entire roof is completed; and then excavating beneath said Aroof to form a tunnel.

2l. The method of constructing a tunnel, which comprises: forming underground passage means 0 of substantially less width than the desired width of the tunnel inwardly from a working face; widening said passage means at the inner end thereof to form a transverse arcuate chamber of a width greater than said desired tunnel width and of a height about equal to the desired roof thickness; introducing roof forming material into said chamber to provide an arched roof section of the desired thickness; successively forming similar transverse chambers working toward the outer end of said passage means and successively introducing roofing material into said chambers to form adjoining arched roof sections until the entire roof is completed; and then excavating 5 beneath the arched roof to form a tunnel,

CHARLES D. JACOBS 

